package polymorphism;

class Useful{
	public void f(){}
	public void g(){}
}
class MoreUseful extends Useful{
	public void f(){}
	public void g(){}
	public void u(){}
	public void v(){}
	public void w(){}
}
public class RTTI {
  public static void main(String[] args) {
	Useful[] x = { new Useful(),new MoreUseful()};
	x[0].f();
	x[1].f();
	//x[1].u();
	((MoreUseful)x[1]).u();
	((MoreUseful)x[0]).u();
  }
}
